What causes the throat to wear out faster?

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by elmerdeer, Jan 18, 2009.

  1. elmerdeer

    elmerdeer Well-Known Member

    Jan 21, 2007
    I would like to know what will cause the throat to wear out faster, Is it firing a lighter bullet with faster speed or a heavier bullet thats slower but has a longer bearing surface?
    Examples; 140 accubond at 3250fps or a 160 accubond at 3000fps from a 280AI, with RL-22?
    Just curious.

  2. Coyboy

    Coyboy Well-Known Member

    Jan 30, 2005
    That's a good question, but one that would be hard to answer. So many variables come into play. If the 2 bullets were fired in the same temps, at the same rate, with the same pressure, in the same barrel steel, with the same powder, my bet is the difference would not be much.

    On there own things like, barrel steel quality, powder type, excessive pressure, and rates of fire, would have a greater effect on one barrel outlasting the other.

  3. Derek M.

    Derek M. Well-Known Member

    Jul 12, 2004
    The shortest answer to throat erosion is heat. Usually that means faster, hotter loads. With the 2 loads you suggest, I think it's too difficult to predict.
  4. KQguy

    KQguy Well-Known Member

    Dec 7, 2007
    I was told by one of the guy's that work for Sierra,that loads with heavier bullets will burn out a throat faster than a load with a light fast bullet.He said it was because the heavy bullet load burns longer on the throat,vs. the light bullet load that gets burned up faster.I am sure you will get different opinions,but that one made sense to me.
  5. 3006savage

    3006savage Well-Known Member

    Jul 16, 2008
    I doubt the bullet weight matters at all if you are using the same powder. I think the biggest factor for barrel life in a particular cartridge is the burning temperature of the powders you choose. The throat erosion is caused more by heat than the bullets bearing surface. Some ball powders claim to have cooler burning temps and they should extend barrel life. I also would expect heavier "compressed" loads to produce more heat than a 75% filled case and be tougher on the throat.